A nut, flat on top and bottom having 6 flat sides. For items which have internal tapered or straight (parallel) pipe threads, specific electrical conduit size designation, and which when installed, provide a method of tightening to lock the connection, see locknut, electrical conduit. See also locknut, tube fitting. For items having a thickness (or height) exceeding two times the width across the flats, use post, electrical-mechanical equipment. (when height or thickness and/or width across the flats is designated as a tolerance dimension, the maximum dimension will be used to determine compliance.)
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NATO Maintenance and Supply Agency Classification: Nuts of iron or steel
NSN 5990-00-518-0684
NSN 5975-01-007-7323
NSN 5960-00-361-8409
NSN 5960-01-500-6615
NSN 5990-00-149-8181
NSN 5985-00-590-7980
NSN 5935-01-113-8315
NSN 5915-01-325-9426
NSN 5960-00-757-0126
NSN 5855-01-325-9507
NSN 5835-00-034-4976
NSN 5915-01-181-7325